1. Field of the Invention
The present invention relates to a method for producing a nitride semiconductor optical device and a method for producing an epitaxial wafer.
2. Description of the Related Art
Japanese Unexamined Patent Application Publication No. 2002-43618 discloses a nitride semiconductor light-emitting device. In its embodiments, light-emitting diodes are produced on a c-plane sapphire substrate and a GaN substrate. In the production of the nitride semiconductor light-emitting device, after a 2-nm-thick In0.15Ga0.85N well layer is grown at 750° C., a 3-nm-thick GaN barrier layer is grown while the temperature is increased from 750° C. to 1,050° C. Then a 12-nm-thick GaN barrier layer is grown at 1,050° C. The light-emitting diode has a peak wavelength of about 460 nm.
Japanese Unexamined Patent Application Publication No. 10-12922 discloses a group III-nitride light-emitting device. A light-emitting layer of the group III-nitride light-emitting device is formed on a c-plane sapphire substrate and includes an AlGaN barrier layer and an InGaN well layer. The AlGaN barrier layer is grown at 1,100° C. The InGaN well layer is grown at 800° C.
Japanese Unexamined Patent Application Publication No. 10-135514 discloses a group III-nitride light-emitting device. A light-emitting layer of the group III-nitride light-emitting device is formed on an a-plane sapphire substrate and includes a GaN barrier layer and an InGaN well layer. The GaN barrier layer is grown at 900° C. The InGaN well layer is grown at 750° C.
Japanese Unexamined Patent Application Publication No. 06-268257 discloses a light-emitting diode formed on a c-plane sapphire substrate. In the production of an active layer of the light-emitting diode, the growth temperature of an InGaN well layer is the same as that of an InGaN barrier layer, which is 800° C.
Japanese Unexamined Patent Application Publication No. 11-224972 discloses a light-emitting diode formed on a c-plane sapphire substrate. In the production of an active layer of the light-emitting diode, the growth temperature of an InGaN well layer is the same as that of an InGaN barrier layer, which is 750° C.